A Novel Hybrid Class E Topology with load-independent Output for WPT

Abstract

Class E circuit has the advantages of less components, high reliability and soft switching, but the traditional Class E circuit can only be used in low power condition because of the unidirectional excitation. In order to extend the power range, this paper proposes a novel hybrid Class E circuit, which can be operated at high power. Moreover, the proposed topology can achieve constant current (CC) and constant voltage (CV) output by switching the branch once without changing the switching frequency or compensation network. Compared with the existing CC and CV scheme, it has the advantages of less components, simple control and high stability. In this paper, the working principle of the circuit is analyzed, and the variable zero-voltage switching (ZVS) margin is introduced to make the calculation of parameters design method more accurate. Subsequently, the influence of higher order harmonics on the circuit and the sensitivity of parameters is analyzed. Finally, an 180W experimental platform with CC and CV characteristics is built to verify the feasibility of the circuit and the accuracy of theoretical analysis.